Rick Smith, Taser International's chief executive, called Cover "one of the most influential inventors of modern times."

The Taser issues darts attached to wires that deliver electric shocks that temporarily subdue aggressive suspects. While the device has become a common tool for police officers, it is still controversial because it has been linked to a number of deaths.

Cover, a one-time NASA scientist, began developing the Taser as a nonlethal weapon to combat the hijackings and riots that were happening in the 1960s, Smith said.

He derived its name from a fictional weapon in a favorite childhood book, "Tom Swift and His Electric Rifle," one of a series of adventure stories by Victor Appleton.

"What an amazing thought, stunning people with blue balls of electricity," Cover told The Washington Post in 1976, recalling his fascination with the book. He said that an "A'' was added to the name of his invention because "we got tired of answering the phone 'TSER' for Tom Swift's Electric Rifle."

The Los Angeles police department began using the devices, still somewhat of a novelty, in 1980, and other departments also began using them. More than 13,400 law enforcement, correctional and military agencies in 44 countries now use Taser guns, according to Taser International's Web site.

The Taser's popularity grew after Smith and his brother Tom contacted the inventor in the early 1990s. Working together, they developed a new version that used compressed air, rather than gun powder, to propel the darts.

But critics note that numerous suspects have died in confrontations in which the Taser has been used. The American Civil Liberties Union is pressing to have it classified as a deadly weapon. Others say the suspects' deaths are really linked to drugs or an underlying health problem.

In 2007, Taser International said that it had won more than 60 wrongful death cases, either beating the lawsuits in court or getting them dismissed with no payout or penalty.